.TH std::wstring_convert::wstring_convert 3 "2024.06.10" "http://cppreference.com" "C++ Standard Libary"
.SH NAME
std::wstring_convert::wstring_convert \- std::wstring_convert::wstring_convert

.SH Synopsis
   wstring_convert() : wstring_convert( new Codecvt ) {}              \fB(1)\fP
   explicit wstring_convert( Codecvt* pcvt );                         \fB(2)\fP
   wstring_convert( Codecvt* pcvt, state_type state );                \fB(3)\fP
   explicit wstring_convert( const byte_string& byte_err,
                             const wide_string& wide_err =            \fB(4)\fP
   wide_string() );
   wstring_convert( const std::wstring_convert& ) = delete;           \fB(5)\fP \fI(since C++14)\fP

   1) Default constructor.
   2) Constructs the wstring_convert object with a specified conversion facet, using
   default-constructed values for the shift state and the error strings.
   3) Constructs the wstring_convert object with a specified conversion facet and
   specified shift state, using default-constructed values for the error strings.
   4) Constructs the wstring_convert object with specified error strings, using new
   Codecvt as the conversion facet and the default-constructed state_type as shift
   state.
   5) The copy constructor is deleted, wstring_convert is not CopyConstructible.

.SH Parameters

   pcvt     - pointer to the conversion facet of type Codecvt (behavior is undefined if
              this pointer is null)
   state    - initial value of the conversion shift state
   byte_err - narrow string to display on errors
   wide_err - wide string to display on errors

   Defect reports

   The following behavior-changing defect reports were applied retroactively to
   previously published C++ standards.

     DR    Applied to      Behavior as published       Correct behavior
   P0935R0 C++11      default constructor was explicit made implicit

.SH Example


// Run this code

 #include <codecvt>
 #include <locale>
 #include <utility>

 // utility wrapper to adapt locale-bound facets for wstring/wbuffer convert
 template<class Facet>
 struct deletable_facet : Facet
 {
     using Facet::Facet; // inherit constructors
     ~deletable_facet() {}
 };

 int main()
 {
     // UTF-16le / UCS4 conversion
     std::wstring_convert<
         std::codecvt_utf16<char32_t, 0x10ffff, std::little_endian>
     > u16to32;

     // UTF-8 / wide string conversion with custom messages
     std::wstring_convert<std::codecvt_utf8<wchar_t>> u8towide("Error!", L"Error!");

     // GB18030 / wide string conversion facet
     typedef deletable_facet<std::codecvt_byname<wchar_t, char, std::mbstate_t>> F;
     std::wstring_convert<F> gbtowide(new F("zh_CN.gb18030"));
 }
